The first oil discovery in the Campos Basin dates from 1974, when the ninth well drilled found Albian carbonate reservoirs (Garoupa Field) under a water depth of 120 m. Oil production started on August 13 th , 1977, from the Enchova Field, which produced to a semi submersible platform moored at a water depth of 124 m. This was the beginning of a successful history that led Petrobras to become a world leader company in petroleum exploration and production in deep and ultra-deep waters. Forty-one oilfields were found between 50 and 140 km off the Brazilian coast (under water depths between 80 and 2,400 m), which produce from a variety of reservoirs, including Neocomian fractured basalts, Barremian coquinas, early Albian calcarenites, and (mostly) late Albian to early Miocene siliciclastic turbidites. These reservoirs were responsible for an average oil production of 1.2 million bpd in the year 2002 (83% of the total Brazilian production), and they are expected to be producing 1.6 million bopd by the end of 2005. The cumulative oil production from the Campos Basin comprises 3.9 billion bbl, and the current proven oil reserves are 8.5 billion bbl (89% of total Brazilian reserves).Deep and ultra-deep water giant fields started to be discovered only in 1984. There was a succession of large discoveries, including Albacora, Marlim, Albacora Leste, Marlim Sul, Barracuda, Caratinga, Roncador and, more recently, Jubarte and Cachalote. The development of these fields has continuously provided new challenges for the reservoir characterization and management in the Campos Basin. These fields are developed with fewer, horizontal and high angle wells, drilled into poorly consolidated reservoirs. The extensive use of 3D seismic as a reservoir characterization tool has optimized well location and allowed the reduction of geological risks. Integration of high-resolution stratigraphic analysis with 3D seismic inversion, geostatistic (stochastic) simulation of reservoir properties constrained by seismic, well log and core data, 3D visualization, and voxel-based automatic interpretation has guided the positioning of horizontal wells through thin (<10-15 m) reservoirs. Additionally, 3D visualization techniques have provided a new environment for teamwork, where seismic, well log, and core data are interpreted and added to detailed 3D geological models and, subsequently, to robust reservoir simulation models.The deepwater subsea wells must be designed to allow high production rates (typically >10,000-15,000 bopd), with lifetime completions to avoid costly interventions. In order to assure high productivity, pressure maintenance must be efficient; if water injection is planned, the hydraulic connectivity between injector and producer wells must be guaranteed by high-quality 3D seismic, well log correlation, and observed pressure profiles. Detailed studies have been made in order to define the distribution and number of wells, since the number of wells strongly affects the net present value of deepwater projects. Wells with expected oil r...

The three oil fields Pampo, Linguado and Badejo are located in the southwesternmost known producing areas of the offshore Bazilian Campos Basin. They were discovered as a result of reflection seismic survey and produce from fractured lower Cretaceous (Neocomian) basalts, coquinas of the Aptian Lagoa Feia Formation, carbonates of the Albian Macae Formation and from Eocene sandstones of the Carapebus Member of the Campos Formation. This work describes the prospects, their results, the main reservoirs, correlations, continuity and diagenetic problems. Two early production system are in operation engaged in gathering a better knowledge of the fields for the planning of a definitive production system. INTRODUCTION The oil fields Pampo, Linguado and Badejo cover a NW-SE trending surface, 17 kilometers long and 3 kilometers wide, comprising roughly 51 square quilometers. They are located 115 kilometer SE of Campos city, in water depths of 85m (Badejo) to 120m (Pampo). (Fig. 1). The present knowledge of the fields was achieved through the results of 41 wells, 27 of which were producers, and a 3D seismic survey. The original in place volumes amount to 142 million cubic meters (894 million bbl-st) of oil 6 and 8,941 × 106 cubic meters (312, 965. 415 × 106 cubic feet) of gas. Two early production systems are collecting the production from 8 wells with an average daily oil production of 5,070 cubic meters (31,890 bbl/d). A third production system is being installed. Accumulated production through December 1982, was 1,550.8 M cubic meters (9,754.3 Mbbl). The main significance of the present work is the possibility of learning the behaviour of non-conventional reservoirs, as fractured basalt and non-marine coquinas underlying conventional reservoirs of marine carbonates and turbiditic sandstones, through early production systems. STRATIGRAPHY The stratigraphic colymn of the area (Fig. 2), as in the Campos Basin1, comprises Mezozoic and Cenozoic rocks. The lowest known section is made up of tholeitic, vesicular locally breccoidal, fractured basalts comprising several lava flows of Neocomian age. The sedimentary section consists of a superposition of four lithostratigraphic units. The Lagoa Feia Formation is composed of alluvial fans, fluviodeltaic and lacustrine sandstones, coquinas and shales overlain by evaporites of Aptian age. Its thickness in the area varies from 90 to 600 meters. The Macae Formation of Albian-Cenomanian age, is made up of oncolitic limestones with minor intercalations of calcilutites, marls, sandstones and shales. According to its depositional history, this formation is subdivided into a lower and an upper unit. The lower Macae represents the Albian shallow carbonate platform system, with 2 oncolitic calcarenities forming offshore shoals (Fig. 3), whereas the upper Macae corresponds to the Cenomanian basinal to slope hemipelagic calcilutites. The thickness of this units in the area varies from 560 to 970 meters. The Campos Formation consists of prodelta and deep water shales (Ubatuba) as well as local sandstones turbidites (Carapebus). Activity of Terciary canyons are remarkably shown by evidence of cut and fill throughout the sequence.

No abstract